'91 CBR600F2 Fueling Advice

[Bubba]

Any old racers/tuners around who might be willing to share some advice about tuning the carbs on the CBR600? Go to the thread here for some background:

http://www.assfaultjunkies.com/showt...-from-the-dead!!!

Long story short, I've been fiddling with the pilot screw settings thinking that with the aftermarket exhaust, the engine was running a little lean, but based on the popping/farting on closed-throttle deceleration--and the sniff test as well--I'm convinced that at least at low RPM/part throttle, it's too rich. Then as the revs go up, there are a several flat spots at different throttle openings plus the engine feels pretty 'soft' above 9K-10K RPM to redline, and I'd guess that means maybe too lean at WFO, but don't know for sure.

What I'm looking for is any resources to tap for tuning info. I'm not trying to track this thing, so NOT looking for max HP, but would like it to run cleanly around town and show a little more guts on the top end. Still running the stock CV carbs--have no idea if the original owner did any tuning as far as different jets/needles when he swapped the exhaust. I did install new rebuild kits all around, although I didn't replace the slide diaphragms as they appeared in good shape.

Thx for any help!!! Ciao--Bubba

[Helmutt]

I'm not too carb saavy, but if it were me I'd start with a rejet and a few dyno pulls to help scope the a/f ratios across the tach range. That way you'd KNOW what jets are in it, where its pulling lean/rich, and where you'd need to adjust your mix screws and jets up or down. Sorry, but I've got no clue to any tuning sources ( other than DTM-Brian ) and nothing else to offer here except I hope ya get it sorted.